Parents of children who have died or been injured while being manhandled, held down or locked up in America's public schools are fighting back.

Dozens have filed lawsuits and many are speaking out publicly to end what they say is an epidemic of harsh measures being used in schools to subdue unruly or aggressive children – many of whom suffer from autism or other disabilities. They are mothers like Sheila Foster, whose 16-year-old son died after being restrained, allegedly for refusing to leave the basketball court at his school in Yonkers, just outside New York City.

"I know I won't feel him hug me anymore, or say, 'I love you, mommy,'" a tearful Sheila Foster, Corey's mother, told ABC News. "Someone has to be held accountable for this because my son is dead. And this shouldn't happen anymore to another child, to another family."

Foster has sued Leake & Watts, a special needs facility for students with behavioral and learning disabilities. The school has defended the actions of its staff, despite the tragic outcome. Surveillance video made public earlier this month shows the teenager playing basketball in the school gym alongside other students and staff members. Minutes later he is surrounded by school staff in a corner of the gym where it appears he is pushed against the wall and then restrained face down by four staff members. Nearly 45 minutes later he was removed from the gym on a stretcher.

"They circled him like thugs or a gang," said the family's lawyer Jacob Oresky in response to the surveillance video. "The staff members at Leake & Watts exercised a lot of force on Corey Foster and they killed him." An autopsy ruled Corey's death an accident, saying he suffered "cardiac arrest during an excited state while being subdued."

Steps taken in other schools to restrain misbehaving children, like the use of locked, padded cell-like rooms sometimes called "scream rooms," have also brought outcries. The mother of a seven-year-old boy in Phoenix, Arizona secretly videotaped the padded room in her son's school after he had been left there for the better part of a school day. She says she later learned he had been held in the room 17 times – though the school disputes that number, saying he was there three times.

"I was disgusted," said Leslie Noyes, the boy's mother. "There was one time that I know he was placed in the room a little after 10 a.m. He was there until the school day ended at 3:30 p.m. They brought him lunch in there. He ate it on the floor. He had urinated on the floor. They wouldn't let him out to use the bathroom."

Officials from the Deer Valley Unified School District said that, because of the pending lawsuit, they could not respond to questions about the case. But in general, spokeswoman Heidi Vega said, seclusion is "the last method of behavior management schools use with a student. Our staff is fully trained on non-violent crisis intervention and puts student safety first at all times. The safety of all students is important and remains a top priority."

In Kentucky, Sandra Baker said she was terrified when she showed up at school to find her son being restrained in what looked like a duffle bag. "Outside the room was the aide and [my son] was completely inside the bag, rolling around in it in the middle of the hallway with other kids around," she told ABC News. "I just kind of stopped and was stunned."

Baker brought her outrage to the local news media.

"One of the reasons why I went on television was because I wanted other parents to be aware that this is going on in the schools and it could be happening to their kids and them not even know about it," she said. "Who's to say he couldn't have possibly died from that … not being able to breathe the way he needs to. Or if he had gotten sick or aspirated or vomited. There are all kinds of things that go through your head when you see that."

The school did not respond to questions about the incident, citing strict privacy rules, but said there have been public misperceptions about what occurred. The bags are designed for restraining children and include breathing holes.

At the Judge Rotenberg Center in Massachusetts, Andre McCollins, a student with autistic characteristics, was restrained face-down on a board with his arms and legs tied down for over six hours and was shocked 31 times using skin-shock therapy. His infraction was refusing to take off his coat.

"I can't believe they call themselves human and do such a thing to someone who is so vulnerable and can't help themselves," lamented Andre's mother Cheryl McCollins in an ABC News interview.

Earlier this year the video of Andre receiving shocks was released after his mother fought for nearly a decade to have it shown. "I'm still angry," said Ms. McCollins. "And I cannot believe that they actually got away with it."

The Judge Rotenberg Center has defended its approach, saying it takes on only the most difficult cases. School officials said the treatment was approved both by Andre's mother and by a court official, and the shocks have proven effective in improving the behavior of children who are prone to harming themselves or are violent to others. It also said it has reduced the number of shocks a student can receive in a given session and no longer applies the shocks while students are strapped to boards.

And while McCollins sued the school and reached a settlement, other parents with children receiving skin-shock therapy at the Rotenberg Center have called the program miraculous. One mother, whose statement was provided to ABC News by the school, said that three years ago her daughter "attacked anyone who came near her, including infants and toddlers."

"Nearly 4 years ago when we brought her to [the Rotenberg Center], she spent about 10 months on a positive only program," the mother's statement says. After petitioning to have her daughter treated with the skin shock therapy, "the impact was almost immediate. She comes home for visits, has a roommate at school, goes out to dinner with staff and friends; she attends classes and enjoys learning and working in the dining hall."

Still reeling from her son's death last spring, Foster has joined forces with parents around the country whose children have been killed or injured as a result of being physically restrained or put into seclusion rooms at school. They are fighting back and speaking up in support of national legislation that seeks to institute a uniform standard on restraint and seclusion for the nation's school.

"There's thousands and thousands of children that have been traumatized, that have been injured at the hands of the caregivers and it's just unacceptable," said Rep. George Miller, D.-California, sponsor of the new legislation.

But school lobbyists opposed to federal legislation say restraint and seclusion techniques are essential in teaching children with autism and other emotional and behavioral disabilities who act out in class and help to keep schools safe.

"There are situations where if you don't have the ability to restrain a child, that child is going to wind up either hurting himself or somebody else," said Daniel Domenech, executive director of the American Association of School Administrators. "There are many cases where the use of seclusion has been in the best interest of the child."

Domenech, who once oversaw the schools in Fairfax County, Virginia, said he agrees that more training is needed to prevent teachers from restraining children in ways that are dangerous. He winced when told of schools that stuffed children in sacks or used duct tape to restrain them.

"Restraint is something that we won't see or don't want to see put in place unless it is absolutely necessary," Domenech said. "But the problem is the training."

The American Association of School Administrators believes restraint and seclusion policies should be decided on a local and state level, leaving the federal government to focus on ensuring school districts have the funding and resources they need to support a variety of approaches to address the issue.

While progress has been made at the state level in strengthening laws and statues, many parents and advocacy groups in support of the federal legislation say it's been too slow and the inconsistencies between and within states leave children with disabilities vulnerable.

Foster remain mystified at how her son could receive an achievement award and hours later die in a setting as carefree as a school basketball court.

"I trusted the counselors as I spoke to them and they told me, 'Corey is doing great,'" said a weary Foster. "I feel betrayed and lied to."

In an email statement, Meredith Barber, director of institutional advancement at Leake & Watts told ABC News, "While the cause of Corey's agitated behavior towards staff that day is unknown, our staff used various de-escalation and re-direction techniques prior to initiating the therapeutic hold, which was performed correctly and in accordance with the state-mandated protocol. The protocol mandates that therapeutic holds are only instituted if an individual poses a danger to himself or others."

"There was nothing therapeutic about that," said Mrs. Foster as she watched the video of her son's final moments. She told ABC News she was unaware of the school's restraint policy. "I didn't know anything about restraint and therapeutic holds until this happened."

The Foster family is suing Leake & Watts for the wrongful death of their son Corey.